Disengageable electrical connector



g- 4, 1970 w. v. PAUZA 3,523,267

DISENGAGEABLE ELECTRICAL CONNECTOR Filed Jan. 24, 1968 4 Sheets-Sheet l Aug. 4, 1970 w. v. PAUZA 3,523,267

DISENGAGEABLE ELECTRICAL CONNECTOR Filed Jan. 24, 1968 4 Sheets-Sheet 23 Aug. 4, 1970 w. v. PAUZA DISENGAGEABLE ELECTRICAL CONNECTOR 4 Sheets-Sheet 5 Filed Jan. 24, 1968 Aug. 4, 1970 w. v, PAUZA DISENGAGEABLE ELECTRICAL CONNECTOR 4 Sheets-Sheet 4 Filed Jan. 24, 1968 United Patent Oboe 3,523,267 DISENGAGEABLE ELECTRICAL CONNECTOR William Vito Panza, Harrisburg, Pa., assignor to AMP Incorporated, Harrisburg, Pa. Continuation-impart of application Ser. No. 626,252, Mar. 27, 1967. This application Jan. 24, 1968, Ser. No. 704,503

Int. Cl. Hk 1/00 US. Cl. 339-47 7 Claims ABSTRACT OF THE DISCLOSURE Disengageable electrical connector for use with a printed circuit board comprises insulating housing having locking boss extending centrally from one side. Contacts are mounted in the housing and have contact head portions adjacent to, and elevated from, one side in surrounding relationship to locking boss. Boss has bayonettype detent mechanism thereon including means for latching boss in assembled relationship to board and controlling the engagement of the contact heads of the terminals with the conducting paths of the board.

BACKGROUND OF THE INVENTION This application is a continuation-in-part of my copending application Ser. No. 626,252, filed Mar. 27, 1967, and now abandoned.

The vast majority of the presently available disengageable connectors for printed circuit boards are adapted to be applied to the edge portions of the board. In common practice, the conductors on the board extend to the edge of the board and the disengageable connector has a plurality of contacts mounted therein in a manner such that when the connectors are mounted on the board, the contacts engage, and make electrical contact with, the conductors.

There is a substantial need for connectors which can be applied to the printed circuit board at locations remote from the edges rather than at the edges although only a limited amount of development work has been done on connectors of this type. The following US. patents show some of the previously proposed disengageable connectors which are adapted to be mounted at locations remote from the edge of a printed circuit board or the like: 3,209,308; 2,793,351; 2,911,610; and 2,774,949.

SUMMARY OF THE INVENTION A preferred embodiment of the present invention comprises a housing of insulating material such as nylon having a centrally located locking boss extending from one side thereof. This locking boss has locking ears extending from its end, the shape of the ears being such that upon insertion of a locking boss through an irregularly shaped open in a printed circuit board and upon rotation of the housing relative to the board, the ears will prevent axial movement of the housing away from the printed circuit board. Additional locking means for locking the housing in its rotated position are provided either in the form of a locking lug mounted on the locking boss or in the form of a latch arm integral with the housing and engageable with a second opening in the printed circuit board.

The present invention also includes an improved contact terminal for the connector described above. The terminal has a generally cylindrical body portion with an integral flange on its end which extends normally of the axis of the body portion. A pair of axially extending slots are provided in the body portion on each side of the flange so that the contact flange pivots about the sections of the body portion which lies between the slots.

A plurality of contact terminals of this type are 3,523,267 Patented Aug. 4, 1970 mounted in suitable cavities in the housing and the conducting path on the printed circuit boards are located such that after rotation of the housing relative to the board, the contact buttons or ends of the terminals will be in engagement with the terminal or end portions of the printed circuit paths.

In the drawings:

FIG. 1 is a perspective view of a connector in accordance with the invention showing a contact terminal exploded from its contact receiving cavity;

FIG. 2 is a side view of the connector of FIG. 1 in alignment with a panel opening;

FIGS. 3 and 4 are similar to FIG. 2 but showing the manner in which the connector is assembled to the printed circuit board;

FIGS. 5, 6, and 7 are views taken along the lines 5-5, 66, and 77 of FIG. 2;

FIG. 8 is a side view of, on an enlarged scale, of the boss portion of the connector when it is mounted on a printed circuit board;

FIG. 9 is a plan view of a panel opening adapted to receive the connector of FIG. 1;

FIG. 10 is a view similar to FIG. 9 but showing the relationship of the locking boss to the panel opening after the connector has been mounted on the panel;

FIG. 11 is a view taken along the lines 11-11 of FIG. 4;

FIG. 12 is a top plan view of the connector block;

FIG. 13 is a view taken along the lines 1313 of FIG. 8;

FIG. 14 is a perspective view of an alternative embodiment of the invention;

FIG. 15 is a top plan view of the housing of the connector of FIG. 14;

FIG. 16 is a plan view of a portion of a printed circuit board and showing the arrangement of the printed circuit paths around an opening which is adapted to receive the locking boss of the connector of FIG. 14;

FIG. 17 is a perspective view illustrating the mounting of the connector of FIG. 14 on a printed circuit board and the manner in which the connector is locked or secured to the board;

FIG. 18 is a perspective view of a further embodiment of the invention;

FIG. 19 is a top plan view of the connector housing of FIG. 18; and

FIG. 20 is a view similar to FIG. 16 showing the arrangement of conductor paths on a printed circuit board which is adapted to receive the connector of FIG. 18.

Referring first to FIG. 1, a connector 2 in accordance with the invention comprises a block 4 of suitable insulation material, such as a relatively firm nylon which can be injection molded, having a plurality of generally cylindrical cavities 6 extending therethrough from its upper or first side 8 to its lower or second side 10. These cavities open into the side of the block as shown at 7 so that the terminated leads 32 can be moved laterally through the openings and into the cavities as illustrated in FIG. 1. The housing or block has a locking boss generally indicated at 12 extending centrally from its lower side 10, this boss having a generally circular cross-section 14 and having a pair of diametrically opposed laterally extending cars 16, 18 on opposite sides of its lower end. In addition, a locking lug 20 is provided adjacent to the side 10 of the housing and integral with this side and with the boss 12. The lug 20 is circumferentially otfset on the boss 12 with respect to the ears 16, 18; in other words, the lug is in axial alignment with a space between the ears.

The ear 16 has a shoulder 22 which is opposed to, and faces, the side 10 of the block 4 and the car 18 has a similar shoulder 24. These shoulders are helically inclined in a common direction towards the surface of the side so that they have ends which are proximate to the surface of the side 10. The helically inclined portions of the shoulders merge with flat portions 22a, 24a which define planes extending normally of the axis of the boss. The lug defines a shoulder 25 which is opposed to the shoulders 22, 24. This shoulder 25 also defines a plane which extends normally of the axis of the boss 12. Axial stops 26, 28 in the form of axially extending ribs are provided on the boss, the stop 28 extending between one side or end of the lug 2t and the end portion 24a of the ear 18 while the stop 26 extends from the end portion 22a of the car 16 to the surface of the side 10 of the block 4.

The block 4 is provided with an axial cavity or bore 27, FIG. 12, which extends downwardly from the upper side 8 to a location adjacent to the lower side of the block. Additionally, openings 29, 31 are provided in the floor of this cavity which openings are in alignment with the cars 16, 18. The openings 27, 29, 31 permit the housing to be made by a relatively simple injection molding process with a single action mold. The openings 29, 31 permit the movement of core pins through the mold cavity so that the shoulders 22, 24 can be formed when the molding material, is injected into the mold. Connector blocks in accordance with the invention can thus be manufactured at high production rates and at an extremely low cost.

A plurality of supporting feet are integral with the side 10 of the housing and project therefrom by an amount slightly less than the spacing between the surface of the shoulder 25 and the surface of the block 10. These feet, as will be explained below, function to stabilize the block when it is mounted on the printed circuit board 48 and prevent overstressing of the contact portions of the terminals 42 as will be explained more fully below.

A preferred form of terminal 32 in accordance with the invention is crimped onto the stripped end of a wire 34 by means of a first crimp 36 and a second crimp connection 38, the crimped connection 36 securing the terminal to the insulation of the wire and the crimped connection 38 securing the terminal to the conducting core of the Wire. The terminal 32 extends axially from the wire end and has a generally cylindrical body portion 40, the diameter of which is substantially equal to, and slightly greater than, the diameter of the cavities 6. A contact button 42 is formed on the end of the terminal and bent rightwardly of the terminal axis, the shape of this contact button being advantageously spherical to facilitate its sliding motion over the board. Slots 46 extend inwardly from the end of the terminal to define a resilient arm 47 and retaining ears 44 extend radially outwardly from the end of the body portions. As illustrated in FIG. 1, when a terminal is positioned in a cavity, these ears project radially beyond the sides of the cavity and prevent further inward movement of the terminal and overstressing of the contact button 42.

As will be explained below, the contact portion 42 is urged against the surface of the printed circuit board in use. Since the contact portion extends from the end of the arm 47 (which is defined by the slots 46) the arm is flexed about its own end when pressure is applied to the contact portion 42. In other words, the contact portion and the arm flex as a unit with respect to the inner end of the arm 47. This arrangement is advantageous in that fiexure of the contact portion with respect to the body portion of the terminal is substantially reduced or eliminated. Flexure of the latter type is undesirable for the reason that the sharp right angle bend will not withstand repeated flexing without failure.

The terminal is dimensioned, relative to the connector block such that when it is properly positioned in a cavity in the block, the surface of the contact button 42 is be tween the ends of the feet 30 and the plane defined by the shoulder 25 of the lug 20 as best shown in FIG. 2. As will be explained below, if these relationships between the surface of the button 42, the surface of the shoulder 25, and the ends of the feet 30 are maintained, the contact button portion 42 of the terminal will be protected from overstressing during assembly of the connector to the board and good contact pressure will be developed when the connector is in its assembled position.

The printed circuit board 48 which is adapted to receive a connector in accordance with the invention, has a plurality of conducting aths 50 which terminate in generally circular contact portions 51 disposed in a circular pattern around a panel opening 52 which is adapted to receive the boss 12 of the housing. This panel opening 52 (FIG. 9) has opposed edge portions 54 which have a diameter substantially equal to, and slightly greater than, the diameter of the circular cross-section of the boss. Diametrically opposed enlarged diameter portions 56, 58 are provided which conform to the cross-section of the cars 16, 18 on the end of the boss. It will be noted that these enlarged portions are of unequal arcuate extent and that the two cars 16, 18 are similarly of unequal arcuate length. It should be noted also that the arcuate extent of the enlarged portion 56 is equal to the arcuate extent of the ear 16 plus the arcuate extent of stop 26. Similarly, the arcuate extent of enlarged portion 58 is equal to the total arcuate extent of car 18 and stop 28. The entire boss can thus be inserted through the panel opening 52 until the shoulder 25 of lug 20 is against the surface of the board, see FIG. 3. The arcuate extent of the lug 20 is the same as the arcuate extent of the car 18, a relationship which gives rise to a detent device for latching the connector to the board as will be described below.

A further dimensional requirement of the preferred embodiment is that the spacing between the surface of the shoulder 25 and the surface of the proximate ends of the cars 16, 18 is substantially equal to, and slightly less than, the thickness of the printed circuit board so that when the boss 12 is inserted through the panel opening 52, the board, and rotated, the shoulders and ears will be slightly compressed and/or the board will be slightly compressed.

In use, appropriate wires and terminals are fitted in the cavity as illustrated in FIG. 1 to make connections to the appropriate ones of the conductors 50 of the board. The connector is thereafter positioned in alignment with the panel opening 52 and the boss is inserted through the opening until the shoulders 22, 24 are on the opposite side of the panel. The conductors 50, in FIGS. 2-4, are on the underside of the panel and the connector is assembled to the board from the underside. The conductors could be provided on the top of the panel and the connector inserted from above. The block or housing is thereafter rotated through an angle of about 75 in the preferred embodiment until the flat portions 22a, 24a of the shoulders 22, 24 are disposed above the surface of the board and the lug 20 in alignment with the enlarged portion 58 of the panel opening. As a result of the cornpression of the block or board, as explained above, which takes place during such rotation, the lug 20 moves a short distance into the panel opening portion 58; in other words, the compression of the cars 16, 18 and the compression of the lug 20 is partially relieved when this lug is in a position to move partially into the panel opening portion 58. This arrangement has the effect of a detent mechanism which latches the connector to the board thereby preventing accidental removal and preventing loosening of the connector under the influence of vibration or other accidental effects.

As previously noted, the surface 42 of the contact terminal is spaced from the surface of the side 10 a distance slightly less than the spacing between the surface of the shoulder 25 and the surface 10. By virtue of this arrangement, the contact surface 42 of the terminal is held slightly spaced from the surface of the board during assembly of the connector to the board, but after the lug 20 is in alignment with the panel opening portion 58,

the connector housing moves slightly towards the board and the contact portions 42 of the terminals are brought into engagement with the ends of the printed circuit paths 50.

FIGS. 14-17 show an alternative embodiment of the invention which is similar to the previously described embodiment in many respects but which differs therefrom in particular respects pointed out below. The same reference numerals, differentiated by prime marks, are used to identify corresponding structural parts of the embodiment of FIG. 1 and the embodiment of FIG. 14 where appropriate. Structural features of the embodiment of FIG. 14 which do not appear in the embodiment of FIG. 1 are identified by unprimed reference numerals.

The connector 2', FIG. 14, comprises a cylindrical housing 4' having a first plurality of contact receiving cavities 6 similar to the cavities 6 of the previously described embodiment. It will be noted that the cavities 6 are located relatively close to the surface of the housing 4' and are spaced-apart around the periphery of the housing. Additional cavities '60 are located at 90 intervals around the circumference of the housing with the cylindrical contact-receiving portions of these cavities 60 being located relatively close to the longitudinal axis of the housing. In the particular embodiment shown, there are provided four cavities 60 and eight cavities 6' so that a total of twelve contact terminals may be mounted in the housing. Housing 2' has supporting feet similar to the feet 30 of the FIG. 1 embodiment and has additional supporting bosses 78 in the center of each cluster of cavities 6', 60.

The connector 2' is adapted to be locked to the printed circuit board 50' upon insertion of the locking boss 12 through the opening 52 and rotating the housing 4' through an angle of 45 as indicated in FIG. 17. Looking of the housing in its rotated position is, in the case of this embodiment, achieved by means of a latch member 62 having a latching arm 66 which extends beyond the second side 10' of the housing and a lever arm 64 which extends relatively upwardly towards the first side. This latch arm is integral with the housing by means of a flexible hinge member so that the lever arm 64 can be depressed to move the latch arm 66. When the boss 12 is inserted through the opening 52 and the housing rotated through the required 45 angle, the latch arm 66 will enter an additional opening 68 adjacent to the opening 52' and lock the housing in its rotated position, and, therefore, to the printed circuit board. When it is desired to remove the connector from the printed circuit board, the upper end of the lever arm 64 is depressed thereby to move the latch arm 66 out of the opening 68 and permit counter rotation of the housing and removal of the locking boss 12' from the opening 52'.

The printed circuit board paths on the board 50 with which the contact terminals in the connector 2' are engaged are preferably arranged as shown in FIG. 16. Four of these paths 72, which extend at right angles to each other, have contact portions 76 at their ends which are located relatively close to the center of the opening 52'. The remaining conducting paths 70 on the printed circuit board 50' have contact portions 74 which are relatively remote from the center of the opening 52'. The contact terminals in the cavity 6 thus Will make electrical contact with the ends of the conductors 70 while the contact terminals in the cavities 60 of the connector will make electrical contact with the conducting path 72.

It should be pointed out that when the connector is mounted on the printed circuit board and rotated, some of the contact terminals in the housing will pass over, and make momentary electrical contact with, conducting paths on the printed circuit board with which they do not make electrical contact in the final circuit arrangement. For this reason, it is desirable to use the connector 2' only under circumstances where such momentary electrical contact between lead wires secured to terminals in the connector 2' and some of the conductors on the printed circuit board 50' would not be harmful. Alternatively, any undesirable effects can be avoided by applying the connector to the printed circuit board and removing it from the printed circuit board only when no power is passing through the conductors 70, 72 of the printed circuit board.

FIGS. 18-20 show a further embodiment of the invention in which this crossing effect is completely avoided. In this embodiment, the connector 2" has a central body portion 4" from which four arms extend radially at 90 intervals. Each arm is provided with a pair of sideby-side spaced-apart contact-receiving cavities 6" which are adapted to receive electrical contact terminals of the type previously described. The embodiment of FIG. 18 may be provided with a locking boss 12" and a locking lug as previously described with reference to the embodiment of FIG. 1 or may be provided with a separate latching member as described with reference to FIG. 14. In either event, the conductors 84, 82 on the printed circuit board 50 are arranged as shown in FIG. 20. The conductors 84 thus have their contact pad portions 85 located relatively remote from the center of the opening 52" so that these conductors will be contacted by the terminals located in the outer cavities 6" of the four arms 80. The conductors 82 have their contact pad portions 83 located relatively close to the center of the opening 52" and will make contact with the contact terminals disposed in the openings 6" which are relatively adjacent to the axes of the connector housing. When the connector is applied to the printed circuit board and the boss 12" is inserted through the opening 52", the contact portions of the terminals will be located between the four groups of conductors shown in FIG. 20. Upon subsequent rotation of the housing through an angle of about 45 the contact portion of the terminals will move onto the pad portions 83, 85 of the printed circuit paths and will not, during such movement, move over an other conductors on the board.

A salient advantage of the invention is that a positive lock between the connector and the board is achieved in all of the embodiments described above. The lock may take the form of the separate locking lug as described with reference to the embodiment of FIG. 1 or may take the form of a latch member as described with reference to FIG. 14. In either event, the connector cannot be removed from the board excepting by a premeditated and deliberate series of manual operations. It should also be noted that the connector housings described above can all be manufactured by injection molding processes which is to say that they could be rapidly and inexpensively produced.and can be manufactured to the extremely close tolerances required in printed circuit board devices. The connectors shown above are all serviceable in that the contact terminals can be readily removed for circuit changes or for replacement when desired. Finally, it should be noted that in all of the embodiments described above, the locking bosses 12, 12, and 12" are centrally disposed on the underside of the housing and occupy very little space. As a result, the peripheral portions of the connector housing, or the arms in the case of the embodiment of FIG. 18, are entirely available for contact cavities and contacts.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only.

What is claimed is:

1. An electrical connector adapted for use with a printed circuit board or the like comprising:

an insulating housing having a plurality of contact-receiving cavities extending therethrough from a first side to a second side,

a locking boss extending from said second side, said locking boss being centrally located on said second side and having laterally extending ear means thereon, said ear means comprising a pair of ears on opposite sides of said boss,

locking means for locking said housing in its rotated position to lock said connector in said rotated position, said locking means comprising a locking lug integral with said second side and integral with said boss, said lug having a cross-section which is substantially similar to the cross-section of one of said ears, said lug being spaced from said ears and being located, relative to the circumference of said boss, between said ears, said connector being adapted to be mounted on a printed circuit board having a thickness greater than the spacing between said ears and said lug and having an irregularly shaped opening which will admit said boss and said ears whereby, upon insertion of said boss and said ears through said opening and upon rotation of said connector, said ears are disposed against the side of said board which is opposite to the side on which said housing is mounted and said lug enters said opening to lock said connector to said board.

2. An electrical connector as set forth in claim 1 wherein said housing comprises a central body portion and a plurality of arms extending radially from said body portion, said boss extending from said body portion and said cavities extending through said arms.

3. An electrical connector as set forth in claim 2 Wherein each of said arms has at least two of said cavities extending therethrough.

4. An electrical connector as set forth in claim 1 wherein said housing is cylindrical.

5. An electrical connector as set forth in claim 4 wherein said cavities are equidistant from the periphery of said housing.

6. An electrical connector as set forth in claim 4 wherein periodic cavities of said plurality of cavities are disposed relatively proximate to the axis of said housing, the remaining cavities of said plurality being relatively remote from said axis.

7. An electrical connector for use -with a printed circuit board or the like comprising:

' an insulating block having a locking boss extending from one side thereof,

said boss having a pair of laterally extending ears on opposite sides thereof,

said ears being spaced from said one side and defining first shoulders opposed to said one side, said first shoulders being generally helically inclined in one direction whereby said first shoulders have proximate ends with respect to said one side,

a locking lug integral with said housing and said boss, said lug defining a second shoulder opposed to said first shoulders, the spacing between the proximate ends of said first shoulders and said second shoulder being substantially equal to, and slightly less than, the thickness of the printed circuit board to which said connector is applied, said locking lug being offset from said ears relative to the circumference of said boss whereby, upon insertion of said boss through an opening in said printed circuit board conforming to the cross-section of said boss and said ears and upon partial rotation of said housing, until said first shoulders are disposed against surface portions of said printed circuit board and said lug is in alignment with a portion of said opening which re ceived one of said ears, said lug moves relatively into said portion of said opening to lock said connector to said printed circuit board.

References Cited UNITED STATES PATENTS 2,572,448 10/1951 Child 339-49 2,911,610 11/1959 Kirk 339-17 3,089,062 5/ 1963 Schulz 317101 3,209,308 9/ 1965 Aquillon.

MARVIN A. CHAMPION, Primary Examiner J. H. McGLYNN, Assistant Examiner U.S. Cl. X.R. 339127 

